The invention described herein may be manufactured, licensed, and used by or for governmental purposes without the payment of any royalties thereon.
1. Field of the Invention
This invention relates to improved means and methods for dispensing bags, such as plastic, paper, aluminum foil, or aluminum foil laminated with plastic. Specifically, it provides systems for dispensing bags, one at a time, from rolls or from bags stacked in a nested configuration, such that the bags are open after detachment from the dispenser.
2. Prior Art
Bags, such as paper, plastic, aluminum foil, or aluminum foil laminated with plastic, for packaging of small objects or bulk materials, are typically produced in rolls wherein individual bags are detached from adjoining bags by pulling and thereby separating the bags along rows of small perforations. The bottom of one bag is typically adjacent to the top of the next bag in the roll. The edges of the bag openings frequently stick together and the bags often are difficult to open. It is often necessary to print directions on the bags to direct the user to the open end.
Several bag dispensing systems of the prior art seek to overcome the inconvenient features of conventional bag dispensing systems. Typical examples are U.S. Pat. Nos. 4,989,732, 5,183,158, 5,363,965, and 5,863,130, which disclose thermoplastic bag packs wherein bags are stacked side-by-side supported by racks and handle support members. None of these patents disclose the features of the present invention.
The bag dispensing systems of this invention seek to overcome the inconvenience of prior art bag dispensing means. In a first embodiment, closed bags are provided in rolls, connected alternately top-to-top and bottom-to-bottom. Each bag is tapered at the sides toward its bottom such that its top-to-top connection with the next bag is wider than the bottom-to-bottom connection. Each top-to-top connection has a row of small, closely-spaced perforations. The separation of one bag from the next bag moves the sides of the bag in relation to one another, thereby making the bag easier to open. Additionally, the tapered shape of each bag makes it easy to identify the top and bottom of the bag without the need for printed instructions on the bag to identify the top or open end of the bag.
In a second embodiment of this invention, a plurality of tapered open bags is nested, with one bag inside the next. The bags are tapered on both sides such that their bottoms are narrower than their tops. Connected to their tops, there are attachment strips that in turn are connected to each other by conventional means such as staples. Rows of closely-spaced perforations located below the attachment strips ensure that each bag is open when separated by pulling and tearing along the row of perforations. In the nested bag stack used in this embodiment, the tapered bags can be either manufactured with a seam that produces a tapering shape for the bag, or bags with straight parallel sides can be folded in such a way as to produce a tapered shape to the bag.
In a third embodiment of the invention, the tapered bags are first manufactured as tapering tubes with the top and bottom of each tube open. A single plastic tab of a width that fits centrally through the narrower bottom opening of the tapered tubes is perforated transversely at intervals. The perforated plastic tab is inserted through the open bottom seam of each tapered tube. The bottom seam of each bag is sealed and attached to the tab by heat welding at a position on the tab such that the weld and seam are located between two transverse rows of perforations. In manufacturing, successive tapered tubes are slipped on over the outside of the other and each tube is heat-welded to the central plastic tab and the bottom opening is sealed by heat-welding to form a seam in one operation. Thus the bags are nested one within the other with the outer bag sealed and welded to the central plastic tab having alternating seams and perforations. The nested array of bags can be placed in a funnel-like dispenser that holds the bags in a position such that the inner bag is open at the top, ready for articles to be placed inside the bag. The lower end of the central plastic tab emerges from the bottom of the lowest bag and is affixed to the central portion of the funnel-like dispenser by a hook or the like.
In dispensing the bags, after filling the bag, the topmost and innermost bag is removed by grasping the upper edge of the bag and pulling the bag upward. The pulling action breaks the central plastic tab along the row of perforations, which tab extends below the welded seam of the topmost bag. The topmost bag and its contents are then free to be removed from the dispenser. The bag that is below the topmost bag is now open and exposed, ready to receive objects placed in it.
In another embodiment, the central tab is tapered such that the tab is increasingly wider below each successive bag. It is thus possible to assure that the weakest point on the central plastic tab is always immediately below the topmost or innermost tapered bag. When constructed in this way, the nested array of bags will always dispense the topmost or innermost bag when a lifting action is exerted on that bag.